Quick Verdict
Vitamin D3
Actually a steroid hormone precursor. Critical for calcium absorption, immune function, hormone production. Widespread d
Evidence: strong (1000+ studies)
Collagen Peptides
Hydrolyzed collagen (types I, II, III) for skin, joint, and connective tissue health. Provides glycine, proline, and hyd
Evidence: moderate (60+ studies)
Side-by-Side Comparison
| Vitamin D3 | Collagen Peptides | |
|---|---|---|
| Category | vitamins | protein |
| Evidence Level | strong | moderate |
| Studies | 1000+ | 60+ |
| Dosage | 1000-5000 IU | 10-20 g |
Stack Compatibility
Vitamin D3: Magnesium (essential cofactor), Vitamin K2 (MK-7), Calcium (if dietary intake low), Zinc
Collagen Peptides: Vitamin C, Hyaluronic Acid, Glycine, Magnesium
Which Should You Choose?
Vitamin D3 has stronger evidence (1000+ studies).